Fix empty reduce with List output and non-List input

[sperlingxx]

For certain aggregation operations, such as: collect_list or collect_set, their output types are List, while their input might not be List. We need to handcraft the the default scalar for this scenario, since make_default_constructed_scalar can not create list scalars.

[codecov]

Codecov Report

Merging #10435 (302cc5b) into branch-22.04 (0be0b00) will increase coverage by 0.01%.
The diff coverage is n/a.

❗ Current head 302cc5b differs from pull request most recent head 909ef19. Consider uploading reports for the commit 909ef19 to get more accurate results

@@               Coverage Diff                @@
##           branch-22.04   #10435      +/-   ##
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+ Coverage         86.13%   86.15%   +0.01%     
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  Files               139      139              
  Lines             22438    22438              
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+ Hits              19328    19331       +3     
+ Misses             3110     3107       -3     

Impacted Files	Coverage Δ
python/cudf/cudf/core/column/numerical.py	94.69% <0.00%> (-0.30%)	⬇️
python/cudf/cudf/core/column/string.py	88.39% <0.00%> (+0.12%)	⬆️
python/cudf/cudf/core/groupby/groupby.py	91.57% <0.00%> (+0.22%)	⬆️
python/cudf/cudf/core/tools/datetimes.py	84.49% <0.00%> (+0.30%)	⬆️
python/cudf/cudf/core/column/lists.py	90.56% <0.00%> (+0.47%)	⬆️

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[sperlingxx]

@gpucibot merge